\documentclass[12pt]{article} \usepackage{geometry} \geometry{a4paper,inner=22mm,outer=22mm,top=26mm,bottom=26mm,} \usepackage{graphicx} \usepackage{authblk} \usepackage{nopageno} \usepackage{lineno} \usepackage[utf8]{inputenc} \usepackage{xcolor} \usepackage{hyperref} \title{Multiplicity dependence of Hyperon and Hypertriton Production in Zr+Zr and Ru+Ru collisions at $\sqrt{s_\mathrm{NN}} = 200\, \mathrm{GeV}$} \author{Dongsheng Li (for the STAR Collaboration) \\ University of Science and Technology of China } \begin{document} \maketitle \linenumbers In heavy-ion collisions, the production mechanism of hypernuclei, bound states of hyperons and nucleons, is still not fully understood. Recent theoretical model calculations show that a systematic measurement of the multiplicity dependence of yield ratios, such as $^{3}_{\Lambda}\mathrm{H}/\Lambda$ and $\mathrm{S}_{\rm 3}=(^{3}_{\Lambda}\mathrm{H}/^{3}\mathrm{He})/(\Lambda/\mathrm{p})$, can provide strong distinguishing power between different production mechanisms and offer insights into the possible connection between hypernuclei production yields and their internal structure. In 2018, STAR recorded a huge sample of about 4 billion minimum bias events from Zr+Zr and Ru+Ru collisions at $\sqrt{s_{\rm NN}}$ = 200 GeV, enabling a detailed investigation of the multiplicity dependence of hyperon and hypertriton production. In this presentation, we present new measurements on hyperons ($\Lambda, \bar{\Lambda}$ and $\Xi^{-}, \bar{\Xi}^{+}$) and hypertriton, including their transverse momentum ($p_\mathrm{T}$) spectra and $p_\mathrm{T}$-integrated yields ($\mathrm{d}N/\mathrm{d}y$), in four different centrality classes of Zr+Zr and Ru+Ru collisions at $\sqrt{s_{\rm NN}}$ = 200 GeV. The hyperon yields will be compared to those in Au+Au collisions to study the system size dependence of strangeness production. The yield ratios of $^{3}_{\Lambda}\mathrm{H}/\Lambda$ and $\mathrm{S}_{3}$ will be shown as a function of multiplicity and compared with model calculations. Physics implications on hypernuclei production mechanism as well as Y-N interaction will be discussed. \end{document}